UNIVERSAL THREE-POSITION CURRENT RELAY Russian patent published in 2021 - IPC H01H51/16 

FIELD: electrical engineering.

SUBSTANCE: invention relates to the field of electrical engineering and can be used to disconnect electric motors with a variable load on the shaft from emergency modes, preventing overheating of the stator windings. The three-position current relay comprises a housing, a retractor armature, a non-ferromagnetic contact rod, movable contacts mounted on the ends of the non-ferromagnetic contact rod, a retractor armature and a non-ferromagnetic contact rod projecting along the center line beyond the ends of the retractor armature, are articulated by a spring located on the non-ferromagnetic contact rod between the locking ring and the inner end of the retractor armature and a nut holding the joint and wrapped on the non-ferromagnetic contact rod protruding from the lower end of the retractor armature, in the body, the cavity of the retractor armature passes into the expanded cavity of the valve, at the border of the transition of the cavities along the perimeter, a shoulder is formed. The lower fixed contact is fixed on the lower traverse, the valve is held by the lower peripheral plane on the shoulder, covers the armature cavity with the formation of a gap between the lower plane of the valve and the upper end of the retractor armature and has the ability to move along a non-ferromagnetic contact rod protruding from the upper end of the retractor armature.

EFFECT: increased reliability of the protection of the electric motor with a variable load on the shaft from overload and a missing phase.

1 cl, 2 dwg